add esp-idf project skeleton

CMakeLists.txt

@@ -0,0 +1,8 @@
+# For more information about build system see
+# https://docs.espressif.com/projects/esp-idf/en/latest/api-guides/build-system.html
+# The following five lines of boilerplate have to be in your project's
+# CMakeLists in this exact order for cmake to work correctly
+cmake_minimum_required(VERSION 3.16)
+
+include($ENV{IDF_PATH}/tools/cmake/project.cmake)
+project(esp32-sequencer)

main/CMakeLists.txt

@@ -0,0 +1,2 @@
+idf_component_register(SRCS "esp32-sequencer.c"
+                    INCLUDE_DIRS ".")

main/esp32-sequencer.c

@@ -0,0 +1,6 @@
+#include <stdio.h>
+
+void app_main(void)
+{
+
+}